We have gift cards enabled, but when a customer applies one to an order we receive an invoice with only the purchased product and the reduced price after the card was applied with no other evidence of a card being used. So for instance an invoice will show that customer purchased a $110 product for just $10 in the subtotal with no evidence of a card being applied on the invoice.
While we use discount codes fairly regularly and they don't have this issue as they show underneath the product on the invoice. So we're unsure why this may be happening. It's causing a bit of confusion.